Google released 52 algorithm updates and changes in April 2012—1.73 per day. The Panda and Penguin updates received the most attention because they affected the most sites, but 50 other updates impacted search results as well. Most were focused on Google’s crusade to improve the quality of sites that rank the highest in their search results, but others included updates to changes in indexing, spelling, sitelinks, sports scores features and more. Of course, April 1st also brought a new round of Google’s April Fools’ pranks including the super geeky 8-bit Google Maps and Google Australia’s Street Roo instead of the usual Street View.

The most important updates in May, however, focused on site quality and spam prevention. First, Google quietly released the Panda 3.5 algorithm update on April 19. The Panda update, named for the Google engineer who developed it, targets sites with thin content or that repost content found on other sites. This 3.5 update is just the latest of the Panda releases that tend to happen every four to eight weeks.

Sites that create fresh, unique content on a regular basis—such as ecommerce sites that release new products regularly and write their own unique product descriptions—shouldn’t have much trouble with Panda updates. Consumer product sites that feature unique content about their branded products as well as blog posts, Twitter feeds and other sources of unique content should likewise have no Panda problems.

A few days later on April 24, Google released another important algorithm update they codenamed “Penguin” that intensified Google’s war on webspam. Three percent of Google’s search rankings were affected in the U.S. The algorithm update seems to have hit sites that have overoptimized anchor text and low anchor text diversity, as well as a high number of links from topically irrelevant sites.